Metal-air battery and method of using the same

A metal-air battery comprising:

• a cell unit provided with a plurality of metal-air battery cells in parallel, each metal-air battery cell being configured to include:
• a metal electrode,
• an air electrode disposed facing the metal electrode, and
• a housing that supports the metal electrode and the air electrode;
• and
• a power generation tank containing an electrolytic solution,
• wherein a handle is further provided on a side of the cell unit, the handle enabling a replacement of the cell unit, and
• wherein a through-hole is formed in each metal-air battery cell to supply the respective cells with electrolytic solution when the cell unit is immersed in the power generation tank, and to discharge externally from the cells into the power generation tank a product produced by a reaction of the metal electrodes and the air electrodes.